Try the NECJ on 2 (1 clip richer) and with 1 turn out on screw.

 

Clip 2 would be leaner again…not richer, be careful. I still think the lean stock NOZJ needle is what helped kill my motor. I ran that needle for ages from new as it worked fine but lacked some grunt.

Try clip 4 on that NECJ. I run 40 pilot, NEDG or NOZG in clip 4 (from the blunt end). 172 main. I can’t remember AS as once set it’s never been off. No spooge.

I do run an S3 high comp head and lower gearing though. 12/51 for hill work. 13/51 for everything else. I also run Exol at 60-1 on Tesco 99. No issues on this oil in 8 different 2t bikes from small bores to 250 enduro and 200-300 trials bikes.

 

Thanks. I've moved the clip down to next to bottom from centre to raise it 1 notch but haven't touched the AS yet. I was going to try it tonight but it's just started pissing down.

I was thinking of taking the next richer needle out with me and swapping it at a cafe 1/2 way round my route.

 

I meant clip 2 - from bottom 🙄

 

You always go from the top....

 

I was talking to one of the guys at Eurotek recently and he said they were running NOZ series jets in their Shercos but he couldn't remember exactly which one.

Are any of the needles I listed anywhere near the NECJ?

 

No. The NOZ series is more aggressive transition. For instance, it your cruising on a light throttle they can be very on/off and shite. NOZ seem to like on or off in my experience. Where you need more 1/8th to 3/4 throttle use, the Suzuki needles are more forgiving and torquey. I see it as NOZ for faster snappy power like on a H&H/MX or Suzuki if long slippery climbs, nocks where you keep the front light under power or pivot turns type stuff. Both will do each type of riding when required.

In the past, I have found that sometimes a lean region in fueling can cause spooge. The reason being you can’t keep the throttle where you need to so you open it a teeny bit wider without knowing but then get too much fuel for the engine speed and load. It must be like 1-3% more but that’s enough to accumulate spooge and eventually it’ll come out the back. It’s the same when you cure it. Spooge won’t stop straight away as you’ll have lots of residual in the pipe.

Also never bother testing jetting in changeable weather like sun/rain. You’ll just chase your ass. Also don’t bother unless you can get that motor fully hot before testing.

In the ideal world you test each region of throttle getting richer till it stutters. Then you go back a teeny bit. To do this for pilot, A/S, diameter, clip and main takes time and a consistent place to test. Also don’t be afraid to test needles with a main fitted. You’ll soon see when you main comes into play as the bike will drown. It’s a nice test.

 

I knew what l meant, hence saying 1 clip richer ...... but l hear ya ....

 

Thanks Pindie. I'll try step by step on the needle and see if I hit an obvious change too far.
I've recently cleaned the exhaust out and repacked the silencer as it was full of spooge as well as replacing the PV cover breather tubing. The breather was dripping oil after every ride.

If I get to the richest clip on the NECJ, is there any point trying the next size up pilot jet and going back to clip position 1 (for example) on the needle, or will that just bugger things up completely?

 

I would say that if you get to the richest clip on the NECJ then you need to look at the suzuki needle chart and go next richest ....... l "think" needles are supposed to work best on centre/3.

As you know, pilot jet has an effect on all circuits, but you cant compensate the needle by using next up pilot.

I always tested pilot by applying the logic that if it was lean/hanging at 1 turn out that l needed to go up a pilot size.

 

Spooge - personally, l never tuned by spooge ...... if its running right but has a small amount then its fine.

 

I would agree but mine was producing silly amounts of spooge and drinking fuel like there was a hole in the tank.

 

The suzuki needles certainly cut down fuel consumption.

Are your reeds ok?

 

I tried a 42 pilot and it was too much. Always stuttering and gurgling. 40 seems the sweet spot as 38 got hot and limited needle choice as it then meant compensating with a richer needle to keep things cool in tight/slow sections.

If you are running 40 pilot and you can run clip 5 on NECJ, I’d say you’re compensating for the leaner diameter with clip setting. This would make me then try NECW in clip 3. This is the next richer diameter but same clip/taper. The richer clip needles (by half a clip) change from neC to neD. Third letter is clip/taper. Last letter is diameter.

Is your float height correct? I’m wondering if you are getting overloaded with fuel that way?

It can be surprising how much of a difference a clip or even half a clip can make when you are close to getting it right. You’ll soon notice when it is too much or not enough. You have to have everything right for this to be obvious. If it were shown on a dyno type graph, the “off” bit would be an ugly dip in the curve rather than following the nice incremental curve.

I’d definitely recommend the S3 high comp power head. It’s marketed as it’ll make the bike angry and top endy. In reality it’s far from that. It just cleans things up and lets you use richer settings, motor stays cooler and the power window is wider.

This is my bike on its current setting in 30 odd degree heat last summer. No stuttering. No lean bogs. Doesn’t overheat. I run no fan. Note the smooth power delivery the G needle brings with the S3 head.

 

I went out last night on a 30 mile loop of road and easy trails. NECJ on clip 4, everything else unchanged. Dry rather than wet, similar temperature.

Definitely more power and urgency but still seems to be running hot. A tiny bit of spooge at the silencer, more a mist than a dribble. PV vent still clear.

I did set the float when the bike was new and it was pretty close ex works, which was much better than previous bikes of all brands. I will check it again to be sure.

Just moved to richest clip position for another try later, if I get time.

Here's how the plug looked this morning, a bit darker than previously. The colour difference on the centre is actual rather than shadowing .

 

Too weak for me.

 

Looks like a 4t plug! It is a positive that you’ve noticed more go by going richer on the clip. This is really only affecting third throttle onwards though roughly. You need to fill the hole in fueling between the 40 pilot and clip setting. That is needle diameter. The last letter.

I think you should try the NECW or NEDW needles.

I wouldn’t be to worried re spooge at this stage. It’ll naturally disappear once you have the jetting right.

The needles you list are all very close to each other and at the lean and clean end of the spectrum apart from N8RG. I’ve no experience of this needle but I’d be inclined to chuck it in there in clip three and go for a rag around the block. You’ll know in the first 200m if it’s a definite no.

Leaner diameters (J & i) mean that just as you’re cracking the throttle it’ll be clean but it’s the least amount of fuel meaning heat and less torque. If you go richer and find the limit you can get to it’ll run much cooler and have more torque. Much nicer to ride as the power will be fuller and creamy.

 

As suggested before, completely agree with next up (richer) needle.

Lean even for a 4t plug imo.

Not wanting to start a 2t oil debate, l tried exol briefly on a carbed 300 and it was more spoogy than anything else l had used. Gave the oil to a matey and his bikes spooge and smoke all increased. Dont know if that might be a factor in reported spooge excess on the beta.

 

I did another 50 mile run last night on clip 5. Another improvement but I haven't checked the plug yet.

There is certainly a hole in the 1st 3rd of the throttle, after that it feels pretty good. I was starting to think that the pilot jet itself might be faulty as it may not be a genuine Keihin. I think I have a spare so may try that just to rule it out.

I'm happy with the Exol oil. I've been using it for years and engines always look healthy when I take the top off. It's about the only constant in the equation at the moment so little point adding more variables.

Does anyone have a spare NECW or NEDW needle I can buy/borrow/steal to have a furkle with, please?

 

This is today's plug colour. Better but not quite there.

 

Not far off.

No needles here anymore, otherwise l'd lend you.

 

Thanks anyway.

Whichever needle I end up with could do with being flexible enough to allow adjustment for the winter when it needs a bit more fuel.

 

Once the jetting is right, you should be ok messing with airscrew alone - unless you ride somewhere with a marked elevation change.

 

P.S - your copy pilot might well be an issue ......

 

I looked at the pilot jet earlier. It's not a genuine Keihin jet but an EBC branded job I bought from a Beta dealer. I've only just put it in so I can't be sure if it's kosher or not.

I reckon I'll replace it just to be sure. No point chasing round and round with needles for the price of a pilot jet.

 

100%. Mine came with a so called 40 pilot. It was a ****** shitter. I took it out. No Keihin genuine markings. Changed it for the real deal. No problem since. 250s like a 40.

Retailers will buy jets as they see fit but my bike had monkey jets not real jets. Jet quality can be very different. It has to be genuine Keihin or don’t bother.

 

100%. Mine came with a so called 40 pilot. It was a ** shitter. I took it out. No Keihin genuine markings. Changed it for the real deal. No problem since. 250s like a 40.

Retailers will buy jets as they see fit but my bike had monkey jets not real jets. Jet quality can be very different. It has to be genuine Keihin or don’t bother.

Over the years I have seen quite some issues with aftermarket jets. Since I had a problem with one myself I never use anything else than a genuine Keihin jet, wether pilot or main jet.

@RudulfHucker 14 mls per liter is unusually much. Normally it should be around 9 or 10 miles per litre. I would try a richer needle and use a genuine Keihin 40 or 42.

The N2ZJ and NECJ have the same diameter.
The difference is the taper profile, which defines the needle family, or "NE". The NECJ holds this dia longer where the N2ZJ tapers faster, making it richer sooner off idle, then it leans out quick, enhancing the "hit" feel all else being equal. The NECJ starts later, tapers more through the mid so it ends up richer in the upper mid and to the tip. Its more linear.

The N1EI has compared to the others a very short straight sector. The N1Ex needles normally give a burbly/blubbery response from closed throttle up to 1/4 throttle as they are very rich down low, but the N1EI is the leanest of the N1Ex needles. From rich to low they are N1EG, N1EF, N1EH, N1EI.

NOZI and NOZJ should work well on the Beta if in clip #2. In clip #3 and #4 they create a lot of spooge but you know that already.
N8Rx is 1/2 clip leaner than N2Zx otherwise identical.

I know it might be wasted money but try to get a NECW, NEDW (1/2 clip richer than NECW) and a NECH. maybe someone can lend you these needles.

The Suzuki needles (NECx/NEDx) are the easiest to understand, have a very logical numbering system and give a very linear feeling due to their tapers from lean to moderate to rich. They normally require a smaller main jet that the N2Zx as their last third is significantly thinner.

 

Thanks Steve! That's really detailed and I shall have to read it a few more times to understand the detail.

I've been out again today with fresh E5 fuel and the same jetting as last time. The jetting has been completely bizarre and all over the place. One minute it's been running really well with good smooth power. The next it was blubbering and stuttering. Spooge has been running out of both the silencer and the PV breather. The breather has pissed oil all over the bottom of the engine and frame. As the same time, the engine has swung from boiling hot to stone cold.

It's almost making me think of buying a TPI! I think I need therapy...

Off 1st thing to see a man about a genuine Keihin pilot....

 

No worries!

I wonder why your jetting gives such different results. Is the carburetor you have installed the OEM 36 Keihin?
Remote analysis is always fishing in muddy waters, unfortunately. After re-jetting the bike needs a while to "react" on the changes, so I really second what Pindie says. But it should not change its behaviour like you described. Something may be wrong. I just don't know what. When did the bike start to make problems? What changes have been made before th problem appeared? Do you have th possibility to get the carb and all of its components ultrasonic cleaned?

It may sound a bit boring but only genuine jets work as intended. People think they save 7 quid buying a Pollini or other aftermarket jets, but those aftermarket jets can be a pain. Some work fine, others don't. Especially when trouble shooting you only can rule faulty jets out if you use genuine ones.
Many riders think that the numbers stamped on the jets are the diameter and use strange jet gauges to measure them. The truth is, the jets are tested on a flow bench and the numbers indicate how much air they let through in a certain time. Cheap jets aren't tested for correct flow and sometimes lead to problems.